Fredrik Montgomery

Uncemented STAR total ankle prostheses. Three to eight-year follow-up of fifty-one consecutive ankles.

Background: The feasibility of replacing the ankle joint has been a matter of speculation for a long time. In recent years, the designs of ankle prostheses have been improved, and three designs, all used without bone cement, currently dominate the market. However, documentation of the clinical results of the use of these prostheses is sparse. We reviewed the intermediate-term results of fifty-one consecutive Scandinavian Total Ankle Replacements (STAR). Methods: Between 1993 and 1999, fifty-one consecutive ankles were replaced with an uncemented, hydroxyapatite-coated STAR total ankle prosthesis. Clinical examination for the present study was performed by one surgeon who had not taken part in the operations. Standardized radiographs were used. Complications and failures were recorded, and patient satisfaction and functional outcome scores were determined for all patients with an unrevised implant. Results: Twelve ankles had to be revised. Seven were revised because of loosening of at least one of the components; two, because of fracture of the meniscus; and three, for other reasons. A component was exchanged in seven of the twelve revisions, whereas the ankle was successfully fused in the other five. An additional eight ankles had radiographic signs of loosening. The thirty-nine unrevised ankles (thirty-seven patients) were examined after thirty-six to ninety-seven months (median, fifty-two months). The patient was satisfied with the result after thirty-one of the ankle replacements, somewhat satisfied after two, and not satisfied after six. The median Kofoed score increased from 39 points before the surgery to 70 points at the time of the follow-up examination. A median follow-up score of 74 points was recorded when the system described by Mazur et al. and the AOFAS (American Orthopaedic Foot and Ankle Society) system were used. The median range of motion was approximately the same preoperatively and postoperatively. The estimated five-year survival rate, with revision for any reason as the end point, was 0.70. When radiographic loosening of either component was used as the end point, the estimated five-year radiographic survival rate was significantly better for the last thirty-one ankles treated in the series (p = 0.032). Conclusions: Total ankle replacement may be a realistic alternative to arthrodesis, provided that the components are correctly positioned and are of the correct size. However, the risks of loosening and failure are still higher than are such risks after total hip or total knee replacement. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Uncemented STAR Total Ankle Prostheses

BACKGROUNDnThe feasibility of replacing the ankle joint has been a matter of speculation for a long time. In recent years, the designs of ankle prostheses have been improved, and three designs, all used without bone cement, currently dominate the market. However, documentation of the clinical results of the use of these prostheses is sparse. We reviewed the intermediate-term results of fifty-one consecutive Scandinavian Total Ankle Replacements (STAR).nnnMETHODSnBetween 1993 and 1999, fifty-one consecutive ankles were replaced with an uncemented, hydroxyapatite-coated STAR total ankle prosthesis. Clinical examination for the present study was performed by one surgeon who had not taken part in the operations. Standardized radiographs were used. Complications and failures were recorded, and patient satisfaction and functional outcome scores were determined for all patients with an unrevised implant.nnnRESULTSnTwelve ankles had to be revised. Seven were revised because of loosening of at least one of the components; two, because of fracture of the meniscus; and three, for other reasons. A component was exchanged in seven of the twelve revisions, whereas the ankle was successfully fused in the other five. An additional eight ankles had radiographic signs of loosening. The thirty-nine unrevised ankles (thirty-seven patients) were examined after thirty-six to ninety-seven months (median, fifty-two months). The patient was satisfied with the result after thirty-one of the ankle replacements, somewhat satisfied after two, and not satisfied after six. The median Kofoed score increased from 39 points before the surgery to 70 points at the time of the follow-up examination. A median follow-up score of 74 points was recorded when the system described by Mazur et al. and the AOFAS (American Orthopaedic Foot and Ankle Society) system were used. The median range of motion was approximately the same preoperatively and postoperatively. The estimated five-year survival rate, with revision for any reason as the end point, was 0.70. When radiographic loosening of either component was used as the end point, the estimated five-year radiographic survival rate was significantly better for the last thirty-one ankles treated in the series (p = 0.032).nnnCONCLUSIONSnTotal ankle replacement may be a realistic alternative to arthrodesis, provided that the components are correctly positioned and are of the correct size. However, the risks of loosening and failure are still higher than are such risks after total hip or total knee replacement.

Arthrodesis of the ankle secondary to replacement.

One hundred total ankle arthroplasties were performed in our department between 1974 and 1994, and of these, 21 have been reoperated on with arthrodesis due to septic or nonseptic failures after 6 months to 15 years (median 40 months). Immobilization using a Hoffman external fixator was the dominating method. The total ankles were of six different designs. Sixteen of the 21 patients suffered from rheumatoid arthritis. Four of the 21 ankles did not fuse whereas 17 did: 13 at the first attempt and 4 after repeat arthrodesis. At the time of the review, two patients had died. Of the remaining 15 patients whose ankles had fused, all but one were satisfied or somewhat satisfied with the result. Twelve of these 15 ankles rated excellent or good according to the Mazur and Kofoed scoring systems. We conclude that arthrodesis can be performed successfully after a failed ankle arthroplasty.

Tibio-talocalcaneal arthrodesis as a primary proce dure using a retrograde intramedullary nail : A retrospective study of 26 patients with rheumatoid arthritis

Background Arthrodesis of the ankle joint using screws or external fixation is often a demanding procedure, notably in patients with rheumatoid arthritis. We investigated whether tibio-talocalcaneal arthrodesis with the use of an intramedullary nail is a safe and simple procedure. Patients and methods We retrospectively reviewed 25 ankles (25 patients) at median 3 (1–7) years after tibio-talocalcaneal arthrodesis because of rheumatoid arthritis. All had been operated on by retrograde insertion of a retrograde nail. 5 types of nail had been used. Complications, functional outcome scores, and patient satisfaction were determined and the radiographs evaluated for healing. Results All but 1 ankle had a radiographically healed arthrodesis. We recorded 3 deep infections, all healed—in 2 cases after extraction of the nail—and the arthrodesis healed in all 3 patients. The average functional scores at follow-up were high, considering that the patients suffered from rheumatoid arthritis. 23 patients were satisfied with the outcome. We found a correlation between the functional scores and the general activity of the disease expressed as a Health Assessment Questionnaire score. Interpretation In patients with rheumatoid arthritis, tibio-talocalcaneal arthrodesis with a retrograde intra-medullary nail results in a high rate of healing, a high rate of patient satisfaction, and relatively few complications.BACKGROUNDnArthrodesis of the ankle joint using screws or external fixation is often a demanding procedure, notably in patients with rheumatoid arthritis. We investigated whether tibio-talocalcaneal arthrodesis with the use of an intramedullary nail is a safe and simple procedure.nnnPATIENTS AND METHODSnWe retrospectively reviewed 25 ankles (25 patients) at median 3 (1-7) years after tibio-talocalcaneal arthrodesis because of rheumatoid arthritis. All had been operated on by retrograde insertion of a retrograde nail. 5 types of nail had been used. Complications, functional outcome scores, and patient satisfaction were determined and the radiographs evaluated for healing.nnnRESULTSnAll but 1 ankle had a radiographically healed arthrodesis. We recorded 3 deep infections, all healed--in 2 cases after extraction of the nail--and the arthrodesis healed in all 3 patients. The average functional scores at follow-up were high, considering that the patients suffered from rheumatoid arthritis. 23 patients were satisfied with the outcome. We found a correlation between the functional scores and the general activity of the disease expressed as a Health Assessment Questionnaire score.nnnINTERPRETATIONnIn patients with rheumatoid arthritis, tibio-talocalcaneal arthrodesis with a retrograde intra-medullary nail results in a high rate of healing, a high rate of patient satisfaction, and relatively few complications.

Risk analysis of occupational factors influencing the development of arthrosis of the knee

The aim of this study was to identify occupational activities important for the development of arthrosis of the knee, taking into account the confounding factors that were suspected or could be recognized. In the archives of the Department of Diagnostic Radiology at the Malmö University Hospital all radiographs of weight-bearing knees of patients with painful knee joints from the period 1982-1986 were reassessed. We found 340 probands, i.e., subjects with arthrosis of the knee of at least grade 1 in the Ahlbäck classification. These probands and their age- and sex-matched controls (680) were analyzed by a validated questionnaire for details of activities at work inducing knee moment over three 15-year-periods as well as their history of knee injuries at work or in their leisure time. The questionnaire was answered by 266 (79%) arthrosis probands and 463 controls (70%). The results of the questionnaire answers and of the recorded history of knee injuries were statistically analyzed by logistic regression. The relative risk of knee arthrosis was slightly increased (RR: 1.9; CI: 1.4–2.7) in probands with weight-bearing knee bending, i.e., dynamic load of the knee joint when bending, whereas knee injuries (meniscectomies and haemarthrosis) were associated with a higher risk. Weight-bearing knee bending corrected for confounders was not a significant factor for knee arthrosis. Overweight was observed to increase the relative risk. A sedentary profession had, on the other hand, a low risk. The knee injuries (66) were, but for 9 probands, sustained in leisure activities, mainly soccer. We thus conclude that work which induces weight-bearing knee bending by itself does not significantly increase the risk of developing arthrosis of the knee – knee injuries and overweight are more important.

How far does prophylaxis against infection in total joint replacement offset its cost

Selection of a cost effective method of prophylaxis against infection for patients undergoing total joint replacement was shown to depend on the number of arthroplasties performed each year at individual hospitals. When 100 arthroplasties were performed each year the prophylactic use of systemic antibiotics minimised the total costs of the department—that is, the combined costs of prophylaxis and reoperation for deep sepsis. Some departments also used local antibiotic prophylaxis in the form of polymethylmethacrylate cement impregnated with gentamicin or a combination of systemic and local prophylaxis at almost as low a total cost and with comparable effect. Selection of a method of prophylaxis should not be determined solely on the basis of reducing costs. When a value was assigned to the effects of loss of health an economic optimum was established that allowed selection of a more costly method of prophylaxis together with further reductions in the incidence of infection and the need for reoperation.

Arthrodesis of the ankle for non-inflammatory conditions--healing and reliability of outcome measurements.

This is a retrospective study of 30 consecutive primary ankle arthrodeses in 29 patients with osteoarthrosis, operated on in our hospital between 1984 and 1994. Two different techniques were utilized: internal fixation with screws or external fixation using Charnley or Hoffman frames. Only 25 ankles in 24 patients were available for clinical examination. They were examined by two independent surgeons on an average of 51 months after surgery (13 to 187 months). Two radiologists separately examined the radiographs that were available — in this case, 29 ankles, without knowledge of clinical data, and 26/29 (89%) were unanimously considered as fused. This is comparable with what is reported in other series. Unanimity among all four observers regarding healing of the arthrodesis occurred in 20/25 ankles (80%). We consider that both a radiological and a clinical evaluation is important for a fair judgement of fusion. We found high consistency among the observers with respect to the clinical scores. However, the consistency was somewhat better for the Mazur than for the Kofoed system.

Treatment of lateral ankle instability with transfer of the extensor digitorum brevis muscle

Ankle sprains are the most common injuries sustained during sports and physical exercise. Treatment is usually conservative because most of these injuries heal without consequence. However, some injuries may be followed by chronic lateral pain and instability, and surgical stabilization is sometimes necessary. In select cases, there is little or no residual ligament or scar tissue remaining for late reconstruction. Proximal transfer of the origin of the extensor digitorum brevis muscle as a substitute for deficient ligament tissue can be used in these difficult cases. During the years 1971 to 1992, 13 ankles in 10 patients underwent surgery using the proximal extensor digitorum brevis muscle transfer method. At follow-up, all the ankles manifested functional stability and were stable with no clinical drawer sign. All had a normal range of motion in the ankle joint but showed a desired decreased supination range of motion throughout the hindfoot and ankle. The functional Karlsson scores were 84.5 +/- 18.8 before injury, 26.4 +/- 18.7 before surgery, and 83.6 +/- 18.7 at follow-up. Thus, the extensor digitorum brevis muscle transfer seems to be a useful alternative method of long-term ankle stabilization in these difficult chronic case; the results correlate well with a few other studies using this method.

Hypertrophic Extensor Digitorum Brevis Muscles Simulating Pseudotumors: A Case Report

Pseudotumors can involve soft tissue or bone, and can lead to difficulty or uncertainty in diagnosis and treatment. The authors describe bilateral hypertrophy of the belly of the extensor digitorum that simulated ganglia.

Knee moment at work : validation of a questionnaire based on knee moment in working life

Classifications of occupations, such as those of the International Labor Organization, have previously been constructed with respect to the physical strain and joint moment to be expected in conjunction in a profession. To detect which occupational activities specifically induce high knee moments, we designed a questionnaire to analyze walking, knee bending, climbing of stairs and ladders, and jumping during three consecutive 15-year exposure periods in the professional lives of 920 consecutive residents [329 men with a mean age of 72 (range 47–96) and 561 women with a mean age of 77 (range 47–96)] drawn from the population records of the City of Malmö. The answers, classified into three categories with respect to knee joint moment, were compared with a classification of the occupations of all probands according to the same principles by three independent specialists in industrial hygiene. The two classifications showed a high degree of agreement, with Cramers V ranging from 0.49 to 0.6, suggesting a co-variance with a common variable, i.e. the true work-related knee moment.